On Sat, Nov 30, 2002 at 01:49:33PM -0800, Michelle Storm wrote:
| This was: Spamassassin Config Questions, as it originated after I
| installed spamassassin. But I'm splitting it off now for 2 reasons.

| 1) Cause it's sort of it's own problem now.

It is.

| 2) Testing to see if it causes another bounce.

It will (more than likely).

| > > The reason the mail was not delivered at this time is:
| > > <[EMAIL PROTECTED]>: unknown user: "debian_user"

The mail bounced because it was attempted to be delivered to
[EMAIL PROTECTED]  However, the server handling the
domain green.hartshorne.net can't find a user named "debian_user".

This is only half of the story, though.  The mail server for
green.hartshorne.net is horridly broken.  There are two locations in
an email for the sender and two for the recipient(s).  One location,
which you are familiar with, is the message headers.  The other is the
envelope.  Just like snail-mail, the message has contents (headers and
body) and an envelope.  Snail-mail works like this :
    1) The postoffice reads the envelope to determine where to deliver it.
    2) If delivery can't succeed, the postoffice reads the envelope to
        see where to return the package with notification of the
        problem.
Email is works the same way.  However, some systems decide that the
envelope isn't good enough.  They rip open and read mail that isn't
theirs, and then decide to deliver the bounce to the sender mentioned
in the headers, not the one on the envelope.

The rest of the story is this :  somehow, at some time, the address
[EMAIL PROTECTED] was subscribed to the list.  Later
that user no longer exists at that domain.  Now you send a message to
the list, and the list dutifully passes it on to all subscribees.  One
thing the list manager does is change the envelope sender so that
bounces will automatically be handled by it.  Instead, that broken
mail server sent the bounce to you since your address is in the "From:"
header.

-D

-- 
Pleasant words are a honeycomb,
sweet to the soul and healing to the bones.
        Proverbs 16:24
 
http://dman.ddts.net/~dman/

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